Elon Musk’s aides, who have taken over the management of the U.S. government’s human resources agency, locked senior public officials out of the computers containing personal data on millions of federal employees, according to two agency executives.

Eleven days after taking the oath of office, Donald Trump launched a sweeping government overhaul, firing and sidelining hundreds of public officials in an effort to cut bureaucracy and replace them with his own loyalists.

Musk, the billionaire owner of Tesla and X, took on the task of downsizing the federal workforce—2.2 million employees. He moved quickly, installing his associates at the agency known as the Office of Personnel Management (OPM).

The two officials, who spoke anonymously to Reuters for fear of retaliation, said that some senior career employees at OPM had their access revoked to certain data systems within the agency. These systems include a massive database (Enterprise Human Resources Integration) that contains birth dates, Social Security numbers, performance evaluations, home addresses, salary grades, and employment history of government employees.

“We have no idea what they’re doing with the computers and data systems. It’s deeply concerning. There’s no oversight. There is a real cybersecurity and espionage risk,” one official said.

The officials who were “locked out” can still log in and access certain services, such as email, but they can no longer view the vast troves of data that cover every aspect of federal employees’ work.

Musk, the OPM, representatives of his new team, and the White House did not respond to requests for comment.

The OPM has sent out memos to employees, departing from the usual dry tone of government announcements, urging public servants to resign and “go on vacation to the destination of their dreams.”

Don Moynihan, a professor at the Ford School of Public Policy at the University of Michigan, said the developments at OPM raise concerns about whether Congress still has oversight of the agency. “It’s becoming increasingly difficult for anyone outside Musk’s inner circle to know what’s going on,” he said.

A group composed of current and former Musk employees took control of OPM on January 20, the day of Trump’s inauguration. They installed sleeper sofas on the fifth floor of the building, where the director’s office is located, according to an agency employee.

The sleeper sofas were placed there so the team could work around the clock.

Musk had previously placed beds in the offices of the X platform after acquiring it in 2022, so employees could work longer hours.

“It feels like a hostile takeover,” one employee remarked.

The newly appointed OPM officials also removed the agency’s chief executive, Kiran Ahuja, from her office and relocated her to another floor.